Aguero has been sidelined with a hamstring injury after picking up the knock while playing for Argentina during the international break in early October and is expected to be sidelined for up to a month.

The former Atletico Madrid man is now approaching a return to action, though Pellegrini insists he will not rush Aguero back into the fray.

"He is improving, but he has some time more to be 100 per cent recovered," Pellegrini is quoted as saying by Manchester Evening News.

"We are trying to have a starting line-up that is the best we can have at this moment. It's not easy because we have so many players injured. Maybe a few players are playing a lot of games."